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Floquet Higher-Order Topological Insulators with Anomalous Dynamical Polarization
Biao Huang1, W Vincent Liu1,2,3,4
1Department of Physics and Astronomy, University of Pittsburgh, Pittsburgh PA 15260, USA.
Physical Review Letters
|June 13, 2020
Summary
This study introduces Floquet driving to higher-order topological insulators (HOTIs), revealing novel dynamical polarization and anomalous multipoles. A method to detect these unique corner states and their origins in cold atom experiments is proposed.
Area of Science:
- Condensed Matter Physics
- Quantum Materials
- Topological Phases of Matter
Background:
- Higher-order topological insulators (HOTIs) feature unique topological properties.
- These properties stem from higher-order multipoles in the bulk, distinct from conventional topological insulators.
- Floquet engineering offers a powerful method to dynamically control material properties.
Purpose of the Study:
- To explore the effects of Floquet driving on higher-order topological insulators.
- To develop a dynamical polarization theory for Floquet-engineered HOTIs.
- To propose experimental methods for detecting novel topological phenomena in cold atom systems.
Main Methods:
- Incorporation of Floquet driving into the theoretical framework of HOTIs.
- Development of a dynamical polarization theory to describe nonequilibrium multipoles.
- Design of a cold atom experimental proposal for detecting anomalous Floquet corner modes.
Main Results:
- A novel dynamical polarization theory for Floquet HOTIs with anomalous nonequilibrium multipoles.
- Demonstration of a method to detect both corner states and their dynamical origin.
- Proposal for experimental realization and verification of anomalous Floquet corner modes.
Conclusions:
- Floquet driving introduces new topological phases and phenomena in HOTIs.
- Anomalous Floquet corner modes and their dynamical origins are theoretically predicted.
- Cold atom experiments provide a viable platform for observing these novel quantum states.
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